The head of the city’s Department of Disability became the fourth manager to leave under Mayor Eric Garcetti.

Regina Houston-Swain, who has been GM for nine years, said she has decided to retire after 32 years with the city.

“I am looking forward to pursuing my personal endeavors and spending time with my aging and ill parents,” Houston-Swain wrote in a letter to her staff, adding she will be working with the mayor’s office during the transition period.

Among her accomplishments, she noted, was preserving the department as a separate entity when there were proposals to eliminate it during the city’s financial crisis.

“I am proud that with help from the disabled community and the decisions by the mayor and council that we were able to make sure the department remained,” Houston-Swain said.

Her retirement will take effect on Jan. 10.

Garcetti issued a statement thanking Houston-Swain for her years of service. “My administration seeks to serve all Angelenos, and ADA-related litigation requires careful attention and planning,” he said. In addition to disability issues, the department deals with AIDS-related matters.

Houston-Swain was paid $142,406 a year in the position.

Garcetti is in the process of reviewing all of the city’s general managers, after asking them reapply for their jobs by submitting a memo running down the mission of their department, past achievements as its head and long-range plans within their purview.

So far, Port General Manager Geraldine Knatz, Fire Chief Brian Cummings and Housing Executive Director Mercedes Marquez have announced they are leaving.